1. Field of the Invention
The present invention relates to a reciprocating piston engine and its link mechanism, which is adapted for various types of engines, compressors, pumps, press machines and like machines.
2. Description of the Related Art
In general, a conventional reciprocating piston engine comprises a slider-crank mechanism, which is constructed of: a piston rectilinearly reciprocating in a cylinder; a connecting rod, which has one of its opposite ends rotatably connected with the piston through a piston pin and the other rotatably connected with a crankshaft. In this construction, the piston has its rectilinear reciprocating motion transmitted to the crankshaft through the connecting rod to convert such reciprocating motion into motion of rotation.
In moving the piston up and down in the conventional reciprocating piston engine, the connecting rod is tilted from the direction in which the piston moves. Due to this tilt of the connecting rod, a so-called piston slapping occurs, which is a big factor in producing vibration, noise and frictional loss in the conventional reciprocating piston engine.
Further, in operation, reciprocating masses in the piston and the connecting rod produce unbalanced motion. Due to such unbalanced motion, vibration and noise occur in the reciprocating piston engine. In case that the engine is of a multiple-cylinder type, unbalance couples of forces in the engine also produce vibration and noise.
As described above, the conventional types of reciprocating piston engines, reciprocating piston compressors, reciprocating piston pumps and the conventional crank mechanisms of press machines and like machines suffer from the above-mentioned problems.
Consequently, it is an object of the present invention to provide a link mechanism adapted for reciprocating piston engines, reciprocating piston compressors, reciprocating piston pumps and press machines and like machines, which mechanism is substantially free from any of the above problems of vibration, noise and friction loss, and is excellent in mechanical efficiency, small in size and light in weight.
According to a first aspect of the present invention, the above object of the present invention is accomplished by providing:
A link mechanism for a reciprocating piston engine and the like, characterized in that:
motions of a pair of cylinder-type pistons moving in opposite directions relative to each other are converted into an oscillating-type rotary motion through an oscillating arm provided with a right and a left portion, which portions are equal in mass and in turning radius of their oscillating-type rotary motions; and
the oscillating-type rotary motion is divided into two equal parts by connecting rod means and transmitted to the link mechanism in which the two equal parts of the oscillating-type rotary motion are converted into a rotary motion of a rotary shaft incorporated in the link mechanism. In this link mechanism, the piston path in operation may be rectilinear or circularly-curved.
According to a second aspect of the present invention, the above object of the present invention is accomplished by providing:
A link mechanism for a reciprocating piston engine and the like, characterized in that:
motions of a pair of circularly-curved-type pistons moving in opposite directions relative to each other are converted into an oscillating-type rotary motion through an oscillating arm provided with a right and a left portion, which portions are equal in mass and in turning radius of their oscillating-type rotary motions; and
the oscillating-type rotary motion is divided into two equal parts by connecting rod means and transmitted to the link mechanism in which the two equal parts of the oscillating-type rotary motion are converted into a rotary motion of a rotary shaft incorporated in the link mechanism. According to a third aspect of the present invention, the above object of the present invention is accomplished by providing:
A link mechanism for a reciprocating piston engine and the like, characterized in that:
motions of a pair of vane-type pistons moving in opposite directions relative to each other are converted into an oscillating-type rotary motion through an oscillating arm provided with a right and a left portion, which portions are equal in mass and in turning radius of their oscillating-type rotary motions; and
the oscillating-type rotary motion is divided into two equal parts by connecting rod means and transmitted to the link mechanism in which the two equal parts of the oscillating-type rotary motion are converted into a rotary motion of a rotary shaft incorporated in the link mechanism.
According to a fourth aspect of the present invention, the above object of the present invention is accomplished by providing:
A link mechanism characterized in that:
an oscillating-type rotary motion of an oscillating-type rotary shaft is divided into two equal parts by connecting rod means and transmitted to the link mechanism in which the two equal parts of the oscillating-type rotary motion are converted into a rotary motion of a rotary shaft incorporated in the link mechanism.
In the link mechanism of the present invention described above, in case that the piston path is rectilinear, the tilt of the connecting rod means from the direction in which the piston rectilinearly reciprocates is very small, so that a lateral pressure imposed on the piston is very small. Further, in case that the piston path is circularly-curved, substantially no lateral pressure is imposed on the piston. In any case, vibration and mechanical noise are negligible in the link mechanism of the present invention.
Further, in the link mechanism of the present invention, torque of the oscillating-type rotary shaft is bisected by the connecting rod means and transmitted to the rotary shaft, i.e., crank shaft, so that any unbalanced motion is completely eliminated. Furthermore, in the link mechanism of the present invention, both the connnecting rod means and the crank shaft are reduced in turning radius, and, therefore improved in rigidity, which reduces vibration and noise. Since a crank pin and the crank shaft are reduced in diameter, frictional loss is also reduced. These reductions in vibration, noise and frictional loss realize the link mechanism of the present invention for converting a reciprocating motion into a rotary motion or vice versa with a high degree of efficiency.